The present invention relates to a plastic closure and more particularly to a press-open side dispensing closure for the dispensing of powdered, granular particulate materials.
The closure is an end press-open side dispensing closure economically produced as a one piece molded plastic closure.
There are numerous examples of molded plastic closures which are used to dispense particulate materials. These closures normally provide for dispensing from the top of the closure and are not side dispensers. However, one piece side dispensing closures for particulate material are well known. These are evidenced by the closures of U.S. Pat. No. 3,469,732 which shows a cover for a condiment container having a side dispensing closure. The closure has a lid being pivotally connected to the top of the closure by a living hinge and the lid has a nail or thumb access piece used to lift the lid. The lid has an arcuate dispensing front wall which extends the width of the cover. The arcuate dispensing front wall has a plurality of holes for dispensing product stored in the container. The arcuate dispensing front wall extends downward from the lid into the container through the upper surface of the cover to prevent the product from escaping except through the holes. Capture or stop means on the arcuate dispensing front wall prevents the lid from being lifted beyond a predetermined extent.
U.S. Pat. No. 3,302,835 discloses a combined shaker dispenser and closure adapted to be positioned within an opening in a container, for example, in an opening in the planar top cover of a cylindrical drum. The closure includes a triangular lid section with the apex of the triangle pointing toward the perimeter edge of the cover. The triangular lid section is pivotally connected to the cover along the base of the triangle. A pair of wall sections extending downward from the lid section into the container run from the base of the triangle to the apex where they intersect. As the lid section pivots, the wall sections are maintained in contact with the perimeter of the opening. A plurality of grooves in the wall sections form vertical channels therein to permit product to dispense when the lid section is in a raised position. The lid section includes a flange-like extension beyond the boundaries of the opening to prevent the product from escaping when the lid section is in its closed position and to permit the user to displace the lid section from the closed position.
A common flaw of the aforementioned closures is that they are difficult to operate using only one hand. Many activities leave only one hand free to open a container and apply the stored product. This flaw is especially troublesome in food and medical applications, where it is desired to keep the container closed except when dispensing to avoid contamination. For example, in food preparation, it may be necessary to dispense items from containers while continuously stirring food in a pan. Similarly, when applying a powdered product to an infant's body (such as when changing a diaper), it may be necessary to hold the infant continuously with one hand. It is often inconvenient to predict the need for the product and prepare the container in advance.
There are a number of reasons why prior art closures are difficult to operate using only one hand. Many are designed to rest flush with the upper surface of the container cover when in the closed position and provide a small tab as the exclusive means for operating the closure. A small cavity is sometimes provided under the tab. The user must insert a finger nail or other thin object into the slit under the tab and apply pressure to pry the closure up into the dispensing position. Ordinarily, a user will secure the container with one hand, and pry with the other hand. It is difficult (and even impossible with some closures) to simultaneously secure the container and pry the closure up. In addition, even with two hands, attempting to operate the closure may cause discomfort or injury to users with long or fragile finger nails.
Closures which are conveniently operated with one hand have been developed in the past, but are more difficult and expensive to manufacture and are poorly adapted for dispensing powdered and particulate products. For example, a known two-piece molded closure suitable for shampoos and other viscous liquid products includes a moving lid piece pivotally connected to a fixed base piece, the moving lid piece having stable open and closed positions. The closure is opened or closed by pressing down on the lid piece on the appropriate side of the pivot points. The fixed base piece has a cylindrical fluid channel for carrying fluid from the container to the lid piece, and the lid piece has a perpendicular fluid channel for carrying fluid from the base piece to a dispensing orifice. In the closed position, a sealing means located in the moving lid piece channel engages the outlet of the base piece fluid channel to prevent fluid flow. In the open position, the sealing means is moved away from the base piece channel to permit fluid to flow therefrom into the lid piece channel for dispensing through the orifice.
This closure is poorly adapted for dispensing particulate and powdered products. Because the fluid channels are long compared to their diameter and because of the perpendicular bend in the channel, the dispensation rate of such products is unacceptably low, the product is readily compacted into the channels, and the channels are easily clogged. Also, product remaining in the channels prevents the lid piece seal from properly engaging the base piece channel, preventing the lid piece from being moved to its closed position. Another problem with this closure is the need for producing two separate pieces and additional manufacturing step of assembling the pieces to form a complete unit.
Thus, there exists the need for an improved side-dispensing closure for particulate or powdered products which is easy and comfortable to operate using only one hand.
It is therefore an object of the present invention to provide a side-dispensing closure for particulate or powdered material having a pivotal push open lid and a plurality of dispensing openings.
It is a further object of the invention to provide a press-open side-dispensing closure adapted for convenient one-hand operation, which closure may be economically manufactured by molding as a single piece.